Attribution is the process of observing people's actions and assigning to them traits, dispositions, or other characteristics, and making inferences about causes, intentions, responsibility, and like properties. Over the past 20 years, psychological theories of attribution have developed from empirical studies. At the same time, philosophers have produced a rich literature on the conceptualization of human action. Much of this literature also deals with attribution. Yet the two lines of investigation, one largely empirical, and the other, largely theoretical, have never been put into juxtaposition with one another. The aim of this proposal is to conduct a thorough review of both the psychological and philosophical literature relevant to attribution theory and research, with the objective of producing a coherent theory of attribution as well as improving research paradigms.